ocfs2: Small refactor of truncate zeroing code

We'll want to reuse most of this when pushing inline data back out to an
extent. Keeping this part as a seperate patch helps to keep the upcoming
changes for write support uncluttered.

The core portion of ocfs2_zero_cluster_pages() responsible for making sure a
page is mapped and properly dirtied is abstracted out into it's own
function, ocfs2_map_and_dirty_page(). Actual functionality doesn't change,
though zeroing becomes optional.

We also turn part of ocfs2_free_write_ctxt() into  a common function for
unlocking and freeing a page array. This operation is very common (and
uniform) for Ocfs2 cluster sizes greater than page size, so it makes sense
to keep the code in one place.

Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
Reviewed-by: Joel Becker <joel.becker@oracle.com>

1 files changed, 12 insertions, 8 deletions

diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c
index fae07672eb18..8416e383197c 100644
--- a/fs/ocfs2/aops.c
+++ b/fs/ocfs2/aops.c
@@ -830,18 +830,22 @@ struct ocfs2_write_ctxt {
 	struct ocfs2_cached_dealloc_ctxt w_dealloc;
 };
 
-static void ocfs2_free_write_ctxt(struct ocfs2_write_ctxt *wc)
+void ocfs2_unlock_and_free_pages(struct page **pages, int num_pages)
 {
 	int i;
 
-	for(i = 0; i < wc->w_num_pages; i++) {
-		if (wc->w_pages[i] == NULL)
-			continue;
-
-		unlock_page(wc->w_pages[i]);
-		mark_page_accessed(wc->w_pages[i]);
-		page_cache_release(wc->w_pages[i]);
+	for(i = 0; i < num_pages; i++) {
+		if (pages[i]) {
+			unlock_page(pages[i]);
+			mark_page_accessed(pages[i]);
+			page_cache_release(pages[i]);
+		}
 	}
+}
+
+static void ocfs2_free_write_ctxt(struct ocfs2_write_ctxt *wc)
+{
+	ocfs2_unlock_and_free_pages(wc->w_pages, wc->w_num_pages);
 
 	brelse(wc->w_di_bh);
 	kfree(wc);